BEOL Based RRAM with one extra-mask for low cost, highly reliable embedded application in 28 nm node and beyond

In this work, we demonstrated a low cost, BEOL based embedded RRAM technology by adding only one extra mask on standard 28 nm logic platform. Satisfactory characteristics such as forming free, high on/off ratio (>100) and high operation speed (<;100 ns) were achieved. Array level performance on thermal stability shows both LRS and HRS exhibit excellent stability at high temperature up to 260 °C. The resistance fluctuation caused by RTN signal and atomic structural change were clarified experimentally. Memory window and reading voltage selection are crucial to diminish the resistance variation. Compared with conventional eFLASH, this BEOL based RRAM technology provides a competitive solution for low power, low cost embedded application in 28 nm node and beyond.